The present invention relates to a structure of the evaporation region of an absorption diffusion type refrigerating circulation and, more particularly, to an arrangement way of a common pipe type evaporator in a refrigerating structure of largely shrunk volume and reduced weight.
A conventional refrigerating circulation system of an air conditioner comprises mainly a titanium heat pipe generator 1, a hydrogen chest 2, a separator 3, a liquid heat exchanger 4, an absorber 5, a dehydrator 6, a condenser 7, an evaporator 8, an air heat exchanger 9, a filter pipe 10, an analyzer 11, a U-shaped pipe 12, a fan 13, and a mineral wool plate 14. Ammonia aqueous solution has a high latent heat to be used as a refrigerant. Because water can absorb a large amount of ammonia vapor at room temperature and pressure, and the absorbed ammonia will divagate from water when water is heated, water is used as an absorptive agent in reverse process. Moreover, hydrogen gas will accelerate the evaporation rate of ammonia to provide low partial pressure for the system. For a system achieving absorption refrigerating circulation through gravity and heat, the whole system is non-mechanical. There will be no action of revolution of compressor, not to mention sound of revolution of compressor.
As shown in FIG. 1, heat is added to the generator 1 to let ammonia vapor divagate from the solution after the titanium heat pipe is electrified. The ammonia vapor having heat will rise along the filter pipe 10 and carry part solution to enter the separator 3, where the vapor and the liquid will separately flow along pipeline 3a and 3b, respectively. The liquid flows into the liquid heat exchanger 4 from the pipeline 3b by gravity, and then reaches the absorber 5. The vapor in the separator 3 descends and diverts to the analyzer 11 from the central pipeline 3a. Because the vapor is lighter, after it rises to the dehydrator 6, if there is still any water or condensed liquid, they will flow downwards to the analyzer 11 and then back into the generator 1. The dehydrator 6 has a plurality of annular baffle plates 6a to block the vapor from carrying liquid upwards.
After passing the dehydrator 6, pure ammonia is obtained to enter the condenser 7, which is divided into a condensing pipe 7a and a condensing pipe 7b. The condensing pipe 7a has fins capable of condensing part of the vapor. Heat in the system is only utilized in upward circulation and only to the condensing pipe 7a. Subsequent circulation relies only on gravity to let pure ammonia flow to the evaporator 8. Additionally, the vapor not condensing at the condensing pipe 7a rises to the condensing pipe 7b and then condenses there. The U-shaped pipe 12 between the condenser 7 and the evaporator 8 is used for storing ammonia liquid. When the storage of ammonia liquid exceeds a predetermined level, the ammonia liquid will flow into the evaporator 8. Because the liquid is affected by gravity, horizontal equilibrium is accomplished.
After the liquid brims the U-shaped pipe 12, it will flow into the evaporator 8. When the ammonia liquid enters the evaporator 8 and forms a thin film of ammonia liquid on a series of horizontal baffle plates 8a, hydrogen gas will fill into the U-shaped pipe 12 to decrease the pressure of the ammonia liquid to a designed standard, so that the ammonia liquid can evaporate at low temperatures. When the ammonia liquid evaporates, it will absorb heat, hence accomplishing the effect of condensation. The vapor will be discharged by the fan 13 and be isolated by the mineral wool plate 14.
The more the hydrogen gas, the less the ammonia vapor, and the lower the temperature thereof. When the ammonia liquid is evaporated and mixed with the hydrogen gas, the mixed gas will be heavier than the hydrogen gas, and will descends into the absorber 5 along an inner pipe 9a of the vapor heat exchanger 9. Simultaneously, the hydrogen gas rising from an outer pipe 9b is refrigerated. Diluted ammonia aqueous solution flowing from the separator 3 via the liquid heat exchanger 4 into the top of the absorber 5 will absorb ammonia vapor once contacting the mixed gas coming from the vapor heat exchanger 9, hence only remaining the hydrogen gas. Because the hydrogen gas is insoluble in water and is lighter, it will rise into the evaporator 8 along the outer pipe 9b of the vapor heat exchanger 9 to mix with the ammonia vapor again. The absorber 5 has fins 5a outside cooled by air. This will refrigerate diluted ammonia aqueous solution and enhance its capability of absorption.
Simultaneously, when diluted ammonia aqueous solution absorbs ammonia vapor, it will also release heat. Therefore, using the air-cooled fins 5a to remove heat will enhance continual circulation of the system. When the weak solution absorbs a large amount of ammonia vapor, it becomes concentrated ammonia aqueous solution and descends to the bottom of the absorber 6, and continually descends back into the generator 1 via the liquid heat exchanger 4 and the analyzer 11 to start another circulation.
The prior art has the following drawbacks. Mutual flow between ammonia liquid, ammonia, and hydrogen gas in the evaporator affects the whole stability, and requires a very long pipeline, which is very uneconomic. Furthermore, the vapor heat exchanger, the liquid heat exchanger, and the absorber also have very long pipelines, hence increasing the flow path of pipeline and the whole volume. Therefore, the prior art has a very large volume, which cannot be reduced. The present invention aims to resolve the above problems in the prior art.
One object of the present invention is to provide a structure of the evaporation region of an absorption diffusion type refrigerating circulation. The evaporator at the evaporation region has a simple shape and structure. An ammonia liquid pipe and a hydrogen pipe are simultaneously arranged in the evaporator. The evaporator has a simple and symmetrical shape, and can be processed easily, hence saving the space thereof. Moreover, because the ammonia liquid pipe and the hydrogen pipe are arranged in the evaporator, heat exchange already occurs during the flowing course, allowing reaction being performed at low temperatures and pressures. Quick flow of ammonia liquid is also enhanced.
When ammonia vapor flows inversely, it can absorb heat quickly. All the above are very good designs of heat exchange, letting the refrigerating temperature at the evaporator be lower, reducing the system weight, and shrinking the volume. Therefore, the present invention can produce smaller refrigerating structures of better operation, letting portable refrigerating structures be feasible.
The refrigerating circulation of the present invention comprises a generator, a rectifier, a condenser, an evaporator, a concentrated ammonia aqueous solution tank, and an absorber. A pipeline of the evaporator is disposed at the evaporation region. When the concentrated ammonia aqueous solution flows out from the concentrated ammonia aqueous solution tank, it is heated to bubble and flow to the pipeline of the condenser to condense into ammonia liquid, which is then guided into the pipeline of the evaporator via the ammonia liquid pipe. The absorber is connected with the concentrated ammonia liquid tank. When the ammonia vapor and hydrogen gas pass through the absorber, the ammonia vapor will be absorbed by diluted ammonia aqueous solution to become into concentrated ammonia aqueous solution in the spiral device.
The concentrated ammonia aqueous solution then flows back to the concentrated ammonia solution tank. The diluted ammonia vapor and the hydrogen gas flow via the airway to the hydrogen pipe, which penetrates into one end of the pipeline of the evaporator. Ammonia liquid and hydrogen gas are simultaneously released out from the other closed end of the pipeline of the evaporator to let the ammonia liquid evaporate and absorb heat, hence performing the reaction of heat exchange to absorb heat and refrigerate. The generated ammonia vapor and hydrogen gas will mix together and flow back into the concentrated ammonia aqueous solution tank via a guide-in pipe.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: